Apparatus for depositing a layer of flowable material underwater



A AYER OF FLOWABLE MATERIAL UNDERWATER Sheet l NVENTORC HERMANUS MEIJERHIS AGENT of 2 I May 27, 1969 3,446,027

' H. MEIJER APPARATUS FOR DEPOSITING A LAYER OF FLOWABLE MATERIALUNDERWATER Filed Aug. 14, 1967 Sheet 2 of 2 FIG. 6

INVENTOR HERMANUS MEIJER BY #Lkfi $18 AGENT United States Patent U.S.C]. 6163 8 Claims ABSTRACT OF THE DISCLOSURE An apparatus for depositingfiowable material, e.g., asphalt, underwater in which a supply conduitextending from the water surface to the point the material is to bedeposited is provided at its lower end with a flow reversing'device,such as a bent tube, having an outlet positioned above the lower end ofthe supply conduit. The flow reversing device thus forms a liquid trapto prevent the ingress of seawater into the supply conduit.

Background of the invention The invention relates to an apparatus forthe deposition of a layer of bituminous material underwater on thebottom or talus of a waterway, by leading a stream of liquid bituminousmass to the bottom or talus of the waterway, or for depositing fiowablematerials on the ocean floor around offshore oil well platforms oraround underwater wellheads or other facilities to prevent erosion.

The invention also relates to an apparatus for the deposition of a layerof bituminous material underwater on the bottom or talus of a waterway,comprising a supply conduit for liquid bituminous mass with at least oneinlet and one outlet.

One method for the deposition of a layer of bituminous material on thebottom of a waterway is known in the art. In this method a liquidbituminous mass is led in a downward direction by means of a supplyconduit before being deposited. In order to overcome difiiculties due topenetration of water into the outlet mouth of the apparatus used for thedeposition, the apparatus described in said specification is providedwith narrowed outlet nozzles, arranged in a row.

The volume flowing from a given opening depends to a great extent on theviscosity of the bituminous mass. This viscosityis, in turn, stronglydependent on the temperature and composition of the mass. Thetemperature may vary at the different openings, for example, because theliquid bituminous mass reaching the outer nozzles has been transportedover a greater distance after leaving the supply conduit than liquidbituminous mass reaching the more centrally located nozzles, andconsequently has been cooled down further. For that reason it is notalways easy to ensure the same outlet volume per time at all nozzles.There is also a risk of one of the nozzles becoming blocked, so that theflow pattern is disturbed, and while it is normally the intention tocover the bed with one continuous layer, there is a risk with the use ofthe known apparatus of gaps occurring in the layer of bituminousmaterial applied. At such points the bed is insuificiently protectedagainst water flows.

Summary of the invention The invention provides an apparatus as referredto hereinbefore, in which the said problems are solved by giving eachparticle of the liquid bituminous mass under the water surface at leastonce a flow in an upward direction. A

particle is to be said to have a flow in an upward direction if itsvelocity or the component of its velocity along a vertical axis isdirected opposite to the gravitation. According to the invention, eachparticle of the liquid bituminous mass must at least once under thewater surface have a flow in an upward direction during transport of theliquid bituminous mass to the bottom or the talus of the waterway.

The invention thus provides an apparatus of the type referred tohereinbefore, the supply conduit at the outlet side being provided witha flow reverse device, which functions as a liquid seal, if filled upwith bituminous mass.

A flow reverse device has an outlet month which, at vertical position ofthe supply conduit, is entirely situated at a higher level than thelevel of the highest point of the inner bend of the flow reverse device.In this flow reverse device the flow direction of each particle of thebituminous mass at least once is changed from downward to upward duringpassage. In general, the particles will enter the flow reverse device indownward direction, and during passage through this device they will atleast once flow in an upward direction, owing to the structure of theflow reverse device.

When flowing through the flow reverse device, there is a level afterpassing of which each particle must have a flow in an upward direction,in order to pass the flow reverse device. This level is called the levelof the highest point of the inner bend of the flow reverse device. Iffilled up with bituminous mass the flow reverse device functions as aliquid seal, no water being able to enter the apparatus in view of thelower specific gravity of the water as compared with the specificgravity of the liquid bituminous mass.

Since the flow reverse device functions as a liquid seal a bituminousmass which automatically shuts out the water, no special dimensions ofthe outlet openings are necessary in order to prevent the entrance ofwater.

It is particularly easy to control the discharge by controlling thesupply of liquid bituminous material to the apparatus. The same amountof material flows into the apparatus as flows out, since the column ofliquid bituminous material in the apparatus remains in equilibrium withthe column of water above the upper edge of the outlet mouth of the flowreturn device. There is no need for any valves in view of the saidliquid seal. The capacity of the supply conduit can also be small. Inthis way the apparatus of the invention is less bulky, and theconstruction is simple and trouble-free. The supply conduit preferablyis a straight tube, in order to secure an unhindered downward flow ofthe liquid bituminous mass supplied.

Description of the drawings A number of preferred embodiments of theapparatus according to the invention are elucidated, by means of thefollowing drawings, in which:

FIGURE 1 is a diagrammatic vertical longitudinal section through anapparatus according to the invention, the flow reverse device beingconstructed as a bent tube;

FIGURE 2 is a plan view of a modified flow reverse device;

FIGURE 3 is a sectional view taken along the line 3-3 of FIGURE 2;

FIGURE 4 is an elevational view in partial section of an apparatusforming another embodiment of the invention;

FIGURE 5 is an elevational view in partial section of still anotherembodiment;

FIGURE 6 is a partial elevational view of an embodiment of the inventionin which the flow reverse device is swivelly mounted;

FIGURE 7 is a sectional view taken along the line 77 of FIGURE 6; and,

3 FIGURE 8 is an elevational view of a modified form of the invention inwhich the flow reverse is pivoted to the supply conduit on an axistransverse to the supply conduit.

Description of the preferred embodiments The apparatus 10 comprises asupply tube or conduit 11 and a bent tube or conduit 12, which isattached to the supply tube. The bent tube is open at the upper side andhas an upper edge 14, which is situated at a higher level than thehighest point of the inner bend 13 of the bent tube.

During operation the apparatus 10 is installed in the water in theupright position. The apparatus is, for example, suspended so as toswivel on a hinge 16 from a power-driven vessel or a movable pontoon 17.The supply conduit 11 is filled at the top with a liquid bituminous massfrom a chute 15. An equilibrium is created between the column ofbituminous mass and the column of water above the upper edge 14, so thatthe same amount of bituminous mass flows out of the apparatus as issupplied to it. At the start of the operation of pouring bituminous massonto a bed under water, the apparatus 10 is raised above water byswivelling it round the hinge 16 in the direction shown by the arrow 18.Above water the bent tube 12 is filled to beyond the highest point ofits inner bend 13 and lowered, while the apparatus 10 is filled upfurther. Care is taken that no water can enter. Once the apparatus 10has reached the desired position above the bed or talus of a river or acanal or the surface of a dyke, the vessel is shifted, while as muchbituminous mass is poured into the supply conduit 11 as is required toform a layer 19 of bituminous mass. Since the bituminous mass is heavierthan water it spreads out as a liquid on the surface of the bottom ortalus and forces the water out. A layer '19 can be very rapidly laidwith the apparatus according to the invention.

The upper edge of the outlet mouth of the bent tube 14 may have a greatlength compared with the diameter of the supply tube, extendinglaterally from the supply tube. FIGURE 2 shows diagrammatically ahorizontal section of this embodiment of the invention. In this way abroad area of the bottom or talus of a waterway can be covered with abituminous layer in one operation. In this case, the liquid surface ofthe bitumen along the upper edge 14 is not flat but somewhat curved,since the viscous flow of the bituminous mass at places at a greaterdistance from the supply tube is decreased in view of temperaturedecrease of the liquid bituminous mass. The upper edge 14 can be adaptedto this curved liquid surface, so that even in these circumstances alayer 19 of a uniform thickness can be laid.

FIGURE 3 represents a vertical section along the line 3--3 of FIGURE 2,showing an upper edge 14 adapted to the curved liquid surface, beinghighest at places nearest to the supply conduit. If the thickness of thelayer at one end of the bent tube 12 is desired to be greater than atthe other end, the apparatus is moved somewhat out of the verticalplane, for instance, by making the cable 21 at one end of the tube 12longer than the other cable 21.

In another embodiment of the apparatus according to the invention, theflow reverse device is constructed as a cistern which is open at thetop, the upper edge of which is entirely situated at a higher level thanthe outlet of the supply conduit at a vertical position of the latter.The apparatus 110 according to FIGURE 4 is an example of such anembodiment. A supply conduit 111 ends in a cistern 112. The cistern 112may have a circular cross-section or have any other form, such as arectangular one. An upper edge having a great length compared with thediameter of the supply conduit is preferred. If the flow of bituminousmass is to be led in one direction, the cistern can be constructed insuch a way that the upper edge in the desired direction of flow of theliquid bituminous mass is lower than the upper edge in other directions.In view of viscosity increase of the liquid bituminous mass at places atgreater distance of the supply conduit, the liquid surface in thecistern may be curved and it may be of advantage to adapt the edge tothe curved liquid surface as discussed above.

If a cistern with a circular cross-section is chosen, from which thebituminous mass can flow out on all sides, as depicted in FIGURE 4, theapparatus is especially suited for local deposition of bituminous mass.

Apparatus 210 depicted in FIGURE 5 differs from apparatus 10 in that thesupply tube 211 and the flow reverse device 212 have part of their wallin common. This apparatus is of more compact design, with the resultthat there is less heat loss.

In another embodiment of the apparatus according to the invention, theflow reverse device or the apparatus as a whole can be swivelled aroundthe axis of the supply conduit or an axis parallel therewith. FIGURE 6represents diagrammatically a vertical longitudinal section of such anembodiment of the apparatus according to the invention, while FIGURE 7depicts a view on a horizontal section taken on the line 7-7 of FIGURE6.

Apparatus 310 has a cistern (which may be a bent tube) 312 extendinghorizontally for some distance from the supply conduit 311. The cisternor bent tube 312 can swivel round the supply conduit 311, or theapparatus as a whole can swivel together round the vertical axis of thesupply conduit 311, in the direction of the arrows 323, so that thebituminous mass flows alternately over the upper edge 314a and the upperedge 314b, as the cistern or bent tube 312 swivels back and forth whilethe apparatus 310 is shifted in the direction of the arrow 324. In thisway a broad coating is laid composed of wide arcs of a circle blendinginto each other. Of course, it is also possible to direct the flow ofthe bituminous mass entirely over the upper edge 314e, by increasing theheight of the other edges of the outlet mouth.

FIGURE 8 represents diagrammatically a vertical section through anapparatus according to the invention provided with means to empty theapparatus at any moment, if desired.

The tank 412 of the apparatus 410 swivels round a shaft 425 between theoperating position shown by unbroken lines and the discharge positionshown by dotted lines. In this way, the apparatus 410 can be emptiedcompletely at any desired moment. In the discharge position the upperedge of the flow reverse device is situated at a lower level than thehighest point of the inner bend thereof and the particles of the liquidbituminous mass leaving the apparatus need not have had a flowdirection, which is in the upward direction or have had an upwardlydirected component.

It is obvious that the apparatus according to the invention can be usedin the oblique position as well as in the vertical position. Theposition of the supply conduit is adapted to the depth of the waterway.The upper edge of the outlet of the flow reverse device is preferablykept at a given distance from the bed by means of a feeler device.

The bituminous mass can be passed to the bed from the upper edge of theoutlet mouth of the fiow reverse device with the aid of a guide means(not shown) comprising, for example, a corrugated plate, thecorrugations of which extend in the direction of flow. This corrugatedplate can be hingeably secured to the upper edge and can drag its lowerend along the bed to be coated.

The apparatus according to the invention may be provided with heatingelements (not shown) for keeping the bituminous mass in the liquidstate. These heating elements will usually not be required. It is,however, advisable to insulate the apparatus according to the inventionwith a view to preventing too great a loss of heat.

It is obvious that the part of the upper edge at the top of the outletof the flow reverse device over which no bituminous mass may flow willbe at a higher level than the part of this upper edge which is equippedfor the discharge of the bituminous mass. Under certain circumstances,for instance, in a test apparatus, the upper edge of the flow reversedevice is preferably divided into sections, which can be secured to theflow reverse device in such a way that they can be adjusted in heightindependent of each other. In this Way the fiow pattern of thebituminous mass flowing from the apparatus can be controlled as desired.

Since no parts of the apparatus according to the invention need to havea narrowed passage, uninhibited flow of the liquid bituminous mass issecured. For that reason liquid bituminous mass with a higher viscositycan be applied, than could be used in known apparatus hitherto. For thesame reasons fillers and aggregates of greater diameter can be used inthe liquid bituminous mass to :be deposited on the bottom or talus of aWaterway, than was possible up till now.

What I claim is: 1. An apparatus for the deposition of a layer offlowable materials underwater comprising:

movable buoyant means carried on the surface of the water; dependingimperforate conduit means carried by said buoyant means and having anupper inlet end above the surface of the water and a lowermost endportion disposed in the water near the point said material is to bedeposited; flow directing means carried by the lowermost end portion ofsaid conduit means and having a material-conveying passageway with flowcommunication therewith for substantially reversing the flow of saidmaterial upwardly from said end portion; said flow directing meansterminating in an outlet means positioned above the lowermost endportion and said passageway; and, supply means in communication with theupper inlet end of said conduit means for supplying said material tosaid conduit means.

2. An apparatus as defined in claim 1 wherein said buoyant meanscomprise a movable vessel.

3. An apparatus as defined in claim '1 wherein said passageway of saidflow directing means being defined by a cup-shaped member concentricallyattached to and spaced from the lowermost end portion of said conduitmeans wherein the rim of said cup-shaped member is higher than thelowermost end portion of said conduit means and defines said inletmeans.

4. An apparatus as defined in claim 1 wherein said flow directing meansis journalled to said lowermost end portion to permit said flowdirecting means to swivel about the axis of said conduit. means.

5. An apparatus as defined in claim 1 wherein said flow directing meansis pivotally attached to said lowermost end portion to permit said flowdirecting means to pivot out of communication with the lowermost endportion about an axis transverse to the axis of said conduit means.

6. An apparatus as defined in claim 1 wherein said conduit means ispivotally attached to said buoyant means.

7. An apparatus as defined in claim 1 'wherein said passageway of saidflow directing means is formed of a bent U-shaped portion continuouswith said lowermost end portion.

8. An apparatus as defined in claim 7 in which said outlet means iselongated in a direction transverse to the centerline of said conduitmeans.

References Cited The Oil & Gas Journal; June 5, 1961; p. 54.

EARL J. WITMER, Primary Examiner.

US. Cl. X.R. 61-1, 37, 72.2

